Laws about an injury

So at my game yesterday the ref was a dickweed. One of the multitude of shitty calls he made was when our fullback was racing his way to their line, and suddenly he blows the whistle and stutters something about a player on the other team being injured, the ball never died, so play never should have stopped because someone was hurt. So I was wondering, is it written somewhere in the laws some specific about this situation?

The guy clearly didn't know what he was doing, but he was obviously biased as well it was kind of stupid I wanted to punch him out. They shouldn't have scored on the tries that they did and we could've gotten a couple more, but we won anyways.

yes, that is a valid reason... but what are the chances of a play being played in one are at all times? even if its a ruck situation, longest it might have been is what? 20-30 seconds?
Play will have to continue untill the next stoppage!

Worst ever example of this kind of crap? Two years ago I'm playing out in this kip of a school, I can't remember the exactly how the situation arose but I end up twenty metres out with a clear run to the line when the ref stops play because: There is a bicycle about two metres over the touchline, and of course if I (or anyone else) ran 20 metres left and jumped the bicycle could have injured me. ******* bicycles, always out to get me.